1. Field of the Invention
The present invention relates to surface curvature detectors. More specifically, the invention is directed to a method and apparatus for detecting the curvature of a reflective surface.
2. Description of the Prior Art
In order to detect the curvature of a surface, the prior art devices have included the use of dial indicators for measuring the displacement of the surface from a reference plane. An electronic curvature measuring apparatus has used the curved surface and a reference surface as capacitor plates with the capacitance of the capacitor being affected by the curvature of the surface being analyzed. While such a electronic tester eliminates the mechanical contact and possible damage necessitated by the dial indicator measuring device and is amenable to as rapid measuring operation, it also is limited in that the reference plate and the surface being analyzed must be electrically conductive in order to provide the electrical conduction for the capacitor form thereby. Accordingly, it would be desirable to provide a method and apparatus for measuring the curvature of a surface without the need for a mechanical contact with the surface and having the attributes of being useful for measuring the curvature of a non-metallic surface and providing a rapid measurement operation.